Dysthymia is a fairly prevalent condition with substantial social costs. As a nosological construct, it is defined and distinguished from major depression primarily on the basis of longitudinal course. Ironically, however, prospective data on the long-term course of dysthymia are extremely limited. The present proposal seeks funding to continue a ten- year naturalistic follow-up study of early-onset dysthymia, with four waves of assessments at 2 1\2-year intervals. Subjects will include 97 outpatients with DSM-III-R primary, early-onset dysthymia and a comparison group of 45 outpatients with non-chronic major depression. Assessments will include structured diagnostic interviews assessing Axis I and II disorders conducted blind to the baseline evaluation, a comprehensive battery of self-report questionnaires, interviews with knowledgeable informants, and review of medical records. The study will address six major issues: (1) the diagnostic stability of dysthymia; (2) the long-term naturalistic course of dysthymia; (3) clinical, psychosocial, and familial predictors of course and outcome; (4) the heterogeneity of early-onset dysthymia; (5) the stability of comorbid anxiety and personality disorders, and their relationship with dysthymia over time; and (6) the long-term course of social adjustment in dysthymia.